1 /* 2 * drivers/net/veth.c 3 * 4 * Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc 5 * 6 * Author: Pavel Emelianov <xemul@openvz.org> 7 * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com> 8 * 9 */ 10 11 #include <linux/netdevice.h> 12 #include <linux/slab.h> 13 #include <linux/ethtool.h> 14 #include <linux/etherdevice.h> 15 16 #include <net/dst.h> 17 #include <net/xfrm.h> 18 #include <linux/veth.h> 19 20 #define DRV_NAME "veth" 21 #define DRV_VERSION "1.0" 22 23 #define MIN_MTU 68 /* Min L3 MTU */ 24 #define MAX_MTU 65535 /* Max L3 MTU (arbitrary) */ 25 26 struct veth_net_stats { 27 unsigned long rx_packets; 28 unsigned long tx_packets; 29 unsigned long rx_bytes; 30 unsigned long tx_bytes; 31 unsigned long tx_dropped; 32 unsigned long rx_dropped; 33 }; 34 35 struct veth_priv { 36 struct net_device *peer; 37 struct veth_net_stats __percpu *stats; 38 }; 39 40 /* 41 * ethtool interface 42 */ 43 44 static struct { 45 const char string[ETH_GSTRING_LEN]; 46 } ethtool_stats_keys[] = { 47 { "peer_ifindex" }, 48 }; 49 50 static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) 51 { 52 cmd->supported = 0; 53 cmd->advertising = 0; 54 ethtool_cmd_speed_set(cmd, SPEED_10000); 55 cmd->duplex = DUPLEX_FULL; 56 cmd->port = PORT_TP; 57 cmd->phy_address = 0; 58 cmd->transceiver = XCVR_INTERNAL; 59 cmd->autoneg = AUTONEG_DISABLE; 60 cmd->maxtxpkt = 0; 61 cmd->maxrxpkt = 0; 62 return 0; 63 } 64 65 static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) 66 { 67 strcpy(info->driver, DRV_NAME); 68 strcpy(info->version, DRV_VERSION); 69 strcpy(info->fw_version, "N/A"); 70 } 71 72 static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf) 73 { 74 switch(stringset) { 75 case ETH_SS_STATS: 76 memcpy(buf, ðtool_stats_keys, sizeof(ethtool_stats_keys)); 77 break; 78 } 79 } 80 81 static int veth_get_sset_count(struct net_device *dev, int sset) 82 { 83 switch (sset) { 84 case ETH_SS_STATS: 85 return ARRAY_SIZE(ethtool_stats_keys); 86 default: 87 return -EOPNOTSUPP; 88 } 89 } 90 91 static void veth_get_ethtool_stats(struct net_device *dev, 92 struct ethtool_stats *stats, u64 *data) 93 { 94 struct veth_priv *priv; 95 96 priv = netdev_priv(dev); 97 data[0] = priv->peer->ifindex; 98 } 99 100 static const struct ethtool_ops veth_ethtool_ops = { 101 .get_settings = veth_get_settings, 102 .get_drvinfo = veth_get_drvinfo, 103 .get_link = ethtool_op_get_link, 104 .get_strings = veth_get_strings, 105 .get_sset_count = veth_get_sset_count, 106 .get_ethtool_stats = veth_get_ethtool_stats, 107 }; 108 109 /* 110 * xmit 111 */ 112 113 static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev) 114 { 115 struct net_device *rcv = NULL; 116 struct veth_priv *priv, *rcv_priv; 117 struct veth_net_stats *stats, *rcv_stats; 118 int length; 119 120 priv = netdev_priv(dev); 121 rcv = priv->peer; 122 rcv_priv = netdev_priv(rcv); 123 124 stats = this_cpu_ptr(priv->stats); 125 rcv_stats = this_cpu_ptr(rcv_priv->stats); 126 127 if (!(rcv->flags & IFF_UP)) 128 goto tx_drop; 129 130 /* don't change ip_summed == CHECKSUM_PARTIAL, as that 131 will cause bad checksum on forwarded packets */ 132 if (skb->ip_summed == CHECKSUM_NONE && 133 rcv->features & NETIF_F_RXCSUM) 134 skb->ip_summed = CHECKSUM_UNNECESSARY; 135 136 length = skb->len; 137 if (dev_forward_skb(rcv, skb) != NET_RX_SUCCESS) 138 goto rx_drop; 139 140 stats->tx_bytes += length; 141 stats->tx_packets++; 142 143 rcv_stats->rx_bytes += length; 144 rcv_stats->rx_packets++; 145 146 return NETDEV_TX_OK; 147 148 tx_drop: 149 kfree_skb(skb); 150 stats->tx_dropped++; 151 return NETDEV_TX_OK; 152 153 rx_drop: 154 rcv_stats->rx_dropped++; 155 return NETDEV_TX_OK; 156 } 157 158 /* 159 * general routines 160 */ 161 162 static struct net_device_stats *veth_get_stats(struct net_device *dev) 163 { 164 struct veth_priv *priv; 165 int cpu; 166 struct veth_net_stats *stats, total = {0}; 167 168 priv = netdev_priv(dev); 169 170 for_each_possible_cpu(cpu) { 171 stats = per_cpu_ptr(priv->stats, cpu); 172 173 total.rx_packets += stats->rx_packets; 174 total.tx_packets += stats->tx_packets; 175 total.rx_bytes += stats->rx_bytes; 176 total.tx_bytes += stats->tx_bytes; 177 total.tx_dropped += stats->tx_dropped; 178 total.rx_dropped += stats->rx_dropped; 179 } 180 dev->stats.rx_packets = total.rx_packets; 181 dev->stats.tx_packets = total.tx_packets; 182 dev->stats.rx_bytes = total.rx_bytes; 183 dev->stats.tx_bytes = total.tx_bytes; 184 dev->stats.tx_dropped = total.tx_dropped; 185 dev->stats.rx_dropped = total.rx_dropped; 186 187 return &dev->stats; 188 } 189 190 static int veth_open(struct net_device *dev) 191 { 192 struct veth_priv *priv; 193 194 priv = netdev_priv(dev); 195 if (priv->peer == NULL) 196 return -ENOTCONN; 197 198 if (priv->peer->flags & IFF_UP) { 199 netif_carrier_on(dev); 200 netif_carrier_on(priv->peer); 201 } 202 return 0; 203 } 204 205 static int veth_close(struct net_device *dev) 206 { 207 struct veth_priv *priv = netdev_priv(dev); 208 209 netif_carrier_off(dev); 210 netif_carrier_off(priv->peer); 211 212 return 0; 213 } 214 215 static int is_valid_veth_mtu(int new_mtu) 216 { 217 return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU; 218 } 219 220 static int veth_change_mtu(struct net_device *dev, int new_mtu) 221 { 222 if (!is_valid_veth_mtu(new_mtu)) 223 return -EINVAL; 224 dev->mtu = new_mtu; 225 return 0; 226 } 227 228 static int veth_dev_init(struct net_device *dev) 229 { 230 struct veth_net_stats __percpu *stats; 231 struct veth_priv *priv; 232 233 stats = alloc_percpu(struct veth_net_stats); 234 if (stats == NULL) 235 return -ENOMEM; 236 237 priv = netdev_priv(dev); 238 priv->stats = stats; 239 return 0; 240 } 241 242 static void veth_dev_free(struct net_device *dev) 243 { 244 struct veth_priv *priv; 245 246 priv = netdev_priv(dev); 247 free_percpu(priv->stats); 248 free_netdev(dev); 249 } 250 251 static const struct net_device_ops veth_netdev_ops = { 252 .ndo_init = veth_dev_init, 253 .ndo_open = veth_open, 254 .ndo_stop = veth_close, 255 .ndo_start_xmit = veth_xmit, 256 .ndo_change_mtu = veth_change_mtu, 257 .ndo_get_stats = veth_get_stats, 258 .ndo_set_mac_address = eth_mac_addr, 259 }; 260 261 static void veth_setup(struct net_device *dev) 262 { 263 ether_setup(dev); 264 265 dev->netdev_ops = &veth_netdev_ops; 266 dev->ethtool_ops = &veth_ethtool_ops; 267 dev->features |= NETIF_F_LLTX; 268 dev->destructor = veth_dev_free; 269 270 dev->hw_features = NETIF_F_NO_CSUM | NETIF_F_SG | NETIF_F_RXCSUM; 271 } 272 273 /* 274 * netlink interface 275 */ 276 277 static int veth_validate(struct nlattr *tb[], struct nlattr *data[]) 278 { 279 if (tb[IFLA_ADDRESS]) { 280 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 281 return -EINVAL; 282 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 283 return -EADDRNOTAVAIL; 284 } 285 if (tb[IFLA_MTU]) { 286 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU]))) 287 return -EINVAL; 288 } 289 return 0; 290 } 291 292 static struct rtnl_link_ops veth_link_ops; 293 294 static int veth_newlink(struct net *src_net, struct net_device *dev, 295 struct nlattr *tb[], struct nlattr *data[]) 296 { 297 int err; 298 struct net_device *peer; 299 struct veth_priv *priv; 300 char ifname[IFNAMSIZ]; 301 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp; 302 struct ifinfomsg *ifmp; 303 struct net *net; 304 305 /* 306 * create and register peer first 307 */ 308 if (data != NULL && data[VETH_INFO_PEER] != NULL) { 309 struct nlattr *nla_peer; 310 311 nla_peer = data[VETH_INFO_PEER]; 312 ifmp = nla_data(nla_peer); 313 err = nla_parse(peer_tb, IFLA_MAX, 314 nla_data(nla_peer) + sizeof(struct ifinfomsg), 315 nla_len(nla_peer) - sizeof(struct ifinfomsg), 316 ifla_policy); 317 if (err < 0) 318 return err; 319 320 err = veth_validate(peer_tb, NULL); 321 if (err < 0) 322 return err; 323 324 tbp = peer_tb; 325 } else { 326 ifmp = NULL; 327 tbp = tb; 328 } 329 330 if (tbp[IFLA_IFNAME]) 331 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ); 332 else 333 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d"); 334 335 net = rtnl_link_get_net(src_net, tbp); 336 if (IS_ERR(net)) 337 return PTR_ERR(net); 338 339 peer = rtnl_create_link(src_net, net, ifname, &veth_link_ops, tbp); 340 if (IS_ERR(peer)) { 341 put_net(net); 342 return PTR_ERR(peer); 343 } 344 345 if (tbp[IFLA_ADDRESS] == NULL) 346 random_ether_addr(peer->dev_addr); 347 348 err = register_netdevice(peer); 349 put_net(net); 350 net = NULL; 351 if (err < 0) 352 goto err_register_peer; 353 354 netif_carrier_off(peer); 355 356 err = rtnl_configure_link(peer, ifmp); 357 if (err < 0) 358 goto err_configure_peer; 359 360 /* 361 * register dev last 362 * 363 * note, that since we've registered new device the dev's name 364 * should be re-allocated 365 */ 366 367 if (tb[IFLA_ADDRESS] == NULL) 368 random_ether_addr(dev->dev_addr); 369 370 if (tb[IFLA_IFNAME]) 371 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ); 372 else 373 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d"); 374 375 if (strchr(dev->name, '%')) { 376 err = dev_alloc_name(dev, dev->name); 377 if (err < 0) 378 goto err_alloc_name; 379 } 380 381 err = register_netdevice(dev); 382 if (err < 0) 383 goto err_register_dev; 384 385 netif_carrier_off(dev); 386 387 /* 388 * tie the deviced together 389 */ 390 391 priv = netdev_priv(dev); 392 priv->peer = peer; 393 394 priv = netdev_priv(peer); 395 priv->peer = dev; 396 return 0; 397 398 err_register_dev: 399 /* nothing to do */ 400 err_alloc_name: 401 err_configure_peer: 402 unregister_netdevice(peer); 403 return err; 404 405 err_register_peer: 406 free_netdev(peer); 407 return err; 408 } 409 410 static void veth_dellink(struct net_device *dev, struct list_head *head) 411 { 412 struct veth_priv *priv; 413 struct net_device *peer; 414 415 priv = netdev_priv(dev); 416 peer = priv->peer; 417 418 unregister_netdevice_queue(dev, head); 419 unregister_netdevice_queue(peer, head); 420 } 421 422 static const struct nla_policy veth_policy[VETH_INFO_MAX + 1]; 423 424 static struct rtnl_link_ops veth_link_ops = { 425 .kind = DRV_NAME, 426 .priv_size = sizeof(struct veth_priv), 427 .setup = veth_setup, 428 .validate = veth_validate, 429 .newlink = veth_newlink, 430 .dellink = veth_dellink, 431 .policy = veth_policy, 432 .maxtype = VETH_INFO_MAX, 433 }; 434 435 /* 436 * init/fini 437 */ 438 439 static __init int veth_init(void) 440 { 441 return rtnl_link_register(&veth_link_ops); 442 } 443 444 static __exit void veth_exit(void) 445 { 446 rtnl_link_unregister(&veth_link_ops); 447 } 448 449 module_init(veth_init); 450 module_exit(veth_exit); 451 452 MODULE_DESCRIPTION("Virtual Ethernet Tunnel"); 453 MODULE_LICENSE("GPL v2"); 454 MODULE_ALIAS_RTNL_LINK(DRV_NAME); 455